Politicians couldn't possibly be as venal, as stupid, as irresponsible or as heartless as portrayed in the 30-second spot.

That Republicans would value this crass, conniving, venial, vapid airhead [Sarah Palin] indicates the direction that the Republican party is headed.

Venial means minor in the circumstances; when speaking specifically of sins, it's a slight sin, such as occasionally getting drunk or giving in to small temptations. (Most would agree that killing at least comes under the "mortal" heading.) Political scientist Jean Bethke Elshtain might be guilty of a venial sin according to the author, but not a venal one.

Venal means corruptible, able to be bribed. Politicians are often described as venal. Adolf Hitler, Fidel Castro, and Saddam Hussein certainly wear that label. Whether Sarah Palin does could be a great conversation starter, as long as you don't mind if it comes to blows. But no one will say she's of slight consequence. Her ability to grab headlines proves that. The last example wants venal, not venial.